1. Field of Invention
The present design is generally related to the collection and display of navigational data for a sailing vessel, more particularly, to a data acquisition system which utilizes a parallel bus to connect a plurality of circuit boards which are in parallel communication with each other and a computer/controller, and which are in turn connected to a plurality of input and output devices.
2. Description of Prior Art
On modern sailing vessels it is necessary to have reliable navigation instruments on board. Traditionally instruments that indicate vessel speed, depth, wind speed and direction have been purchased separately, and each instrument is equipped with it's own display and user interface, typically function keys. The number of instruments available today has increased sharply with the availability of advanced marine radar, GPS receivers, gyrocompasses and chart-plotters. These instruments must be mounted in such a way that they can be viewed easily in the cockpit. These instruments are typically mounted in one of two ways: either a bulkhead mount or a cluster mount around the steering wheel pedestal.
The Bulkhead Mount: This mounting method is achieved by cutting multiple penetrations in the bulkhead of the vessel typically to one side of the main hatchway. The instruments are then mounted in these penetrations where they can be viewed from the wheel or tiller. The instruments are then electrically connected to a power source and the instrument's sensor with wiring and cables. This wiring is generally run on the backside of the bulkhead or inside the boat cabin. Instruments may also be mounted on the surface of the bulkhead with a mounting bracket. In this case the wiring is typically run on the exterior bulkhead surface.
The Pedestal Cluster: This mounting method is achieved by mounting the instruments in some configuration about the steering wheel pedestal. Instruments may be mounted with individual mounting brackets or they may be mounted in a common console. Wiring to these instruments is typically fed through the cockpit floor, and it is strapped to the wheel pedestal and routed to the instruments.
Each method has advantages and drawbacks. Bulkhead mounted devices have wiring that is exposed on the bulkhead exterior surface or inside the cabin where it is unsightly. Protecting this wiring from salt-water corrosion and impact is difficult at best. Further the helmsman's view of a bulkhead-mounted instrument is easily obscured because passengers and crew are usually seated directly by the bulkheads where the instruments are mounted. Instruments mounted on the pedestal are easily viewed, but there is little room for many instruments. Most pedestal-mounted instruments are exposed and can be easily impacted or damaged. Multiple power, antenna and sensor cables are again exposed and unprotected.
With the extraordinary advances in technology today, many improvements have been made in the area of marine instrumentation. Many traditional instruments are now manufactured with serial communication (networking) capability built in. Multiple units can be networked to a laptop computer to assimilate data. Many autopilot units are now capable of serial communication with GPS receivers, chart-plotters and radar units. Mounting and utilizing all these devices in such a way that they are presented in a functional and convenient manner is difficult at best.
The drawbacks to the state-of-the-art methodology are that each instrument is presented in it's own housing, and each instrument must provide it's own display, user interface and power regulation. Also each instrument is mounted separately in a unique location. Connecting all these devices to power sources, antenna, sensors and serial communication systems is a difficult and laborious task. This installation requires large amounts of wiring and cable, which are difficult to conceal, protect and maintain. This approach is expensive, redundant, unsightly and generally tedious to use.